Compasses and dividers.



G. S. EVANS.

GOMPASSES AND DIVIDERS.

APPLICATION FILED MAR. 1a, 1908.

953,026. Patented Mar.29,1910.

wr'tne'sses. Inventor.

UNITED STATES PATENT OFFICE.

CHARLES SUMNER EVANS, OF DAYTON, OHIO.

COMPASSES AND DIVIDERS.

To all whom it may concern:

Be it known that I, CHARLES SUMNER Evans, a citizen of the United States, residmg at Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Compasses and Dividers, of which the following is a specification.

My invention relates to improvements in drafting instruments, and particularly to compasses and dividers of the wing type.

The instrument hereinafter described is especially designed and adapted to use in manual training schools, but it is to be understood that it is not limited to such use, but is equally applicable to the general use of mechanics or craftsmen.

The object of the invention is to greatly simplify the construction as well as the means and mode of operation of such instruments, whereby they will not only be cheapened in construction, but will be rendered more efficient in use, easily operated, and unlikely to get out of repair.

Further objects are to provide in such an instrument locking means so located as to be accessible to the operator when using but one hand in adjusting the device, to provide improved connections for the reversible pencil and point holder, and an eccentrically adjustable center point to provide for finer clegree of adjustment than may be obtainable throu h the adjustment of the pivoted legs.

A further object is to provide an instrument balanced in both weight and appearance. The symmetrical appearance of the instrument is desirable since an important part of manual training is the development of the esthetie sense of the student.

With the above primary and other incidental objects in View as will more fully appear in the specification, the invention consists of the means, parts, construction, and

combination and arrangement thereof, and the mode of operation or their equivalents, hereinafter described and set forth in the claims.

Referring to the drawings, Figure 1 is a perspective view of a drafting instrument embodying the invention. Fig. 2 is a vertical section through one of the legs thereof showing the means of securing the reversible pencil holder in place and the pencil therein. Fig. 3 is a detail side elevation of a portion of the pencil carrying leg. Fig. 4 is Specification of Letters Patent.

Application filed March 16, 190B.

Patented Mar. 29, 1910.

Serial No. 421,509.

a detail of the pivot joint. Fig. 5 is a perspective View of an instrument similar to that of Fig. 1, but embodying sundry modifications. Fig. (5 is a modification of the eccentric center point. Fi s. 7, 8 and 9 are further modifications of tie means for locking the respective legs in their adjusted posltions.

Like parts are indicated by similar charactors of reference throughout the several views.

In constructing the instrument, there are employed two legs 1 and 2, substantially U shaped in cross section. The open sides of said channel like or U shaped legs 1 and 2 are turned inward. The upper ends of the respective legs are bifurcated as at 3 to form ears 1; the ears of one leg overlap those of the other leg, the said legs being pivoted together through the said ears 4 as indicated at 5.

Supported on the pivot 5 intermediate the ears of the respective legs is a pendent member terminating above the pivotal point of the instrument in a handle 7, and carrying at its lower extremity lock mechanism adapted to secure the legs 1 and 2 in their adjusted positions. Carried on each of the legs 1 and'2 is a curved wing 8, the said wings overlapping as shown in Figs. 1 and 5. The wings may be superposed as are the wings 8 in Fig. 1, or may be arranged side by side as the wings 9 of Fig. 5. The wings are preferably pivoted to the respective legs as at 10 of Fig. l, but for economy of manufacture may be formed integral with the supporting leg as in Fig. 5. The curvature of the wings is that of an arc concentric with the pivotal point 5 of the legs 1 and 2. If pivoted to the legs, the wings may be formed straight. v

The locking means for the legs 1 and 2 which is accomplished by clamping the respective wings against movement may be varied in construction, that shown in Fig. 1 being one of the preferable forms. In this construction the pendent member 6 has an eye or loop formed therein adjacent to the lower end, through which eye the respective wings project in opposite directions. The portion of the pendent member 6 below the eye is screw threaded and carries the adjusting nut 11. Slidingly mounted on the pendent member 6 intermediate the wings andthe adjusting nut 11 is a shoe 12 adapted to be pressed into engagement with the wings 8 by the nut 11, whereby said wings 8 will be clamped against movement. To maintain the pendent member 6 in central position, toggle links 13 are pivoted at 14L to the respective legs, and at the opposite ends to a slide 15 mounted on the member 6. By this construction the pendent member 6 is held in position to bisect the angle of the legs at all points of adjustment. Instead of the locking means above described, the wings may be secured against movement by a set screw 16 in the eye portion 17 of the pendent member 6, which screw is adapted to bear on the wings. See Fig. 5. The lower end of the member 6 mlght also be bifurcated, as

in Fig. 7, the wings being extended through said bifurcation and secured by a clamping screw 18 engaging the arms 19 and causing them to impinge upon the wings.

In Fig. 8 is shown a further modification in which the extremity of the member 6 is recessed for the reception of the wings 8. A set screw 20 projects between the respective wings, and engages the member 6. A shoulder 21 is formed on the screw 20 which shoulder is adapted to bear upon the wings as shown. An L shaped clip or washer is interposed between the shoulder 21 and the wings 8, to prevent the relation of the wings being changed by the rotary adjustment of the screw.

In Fig. 9 is shown another form of lock device in which 22 is a keeper through which the wings 8 project. 23 is the pivot adapted to connect the respective legs 1 and 2 corresponding to the pivot 5 of Fig. 1. The pivot member 23 is provided with a transverse opening through which projects the revoluble member 24: corresponding to the member 6 of the principal structure.

The member 24 is shaped at the upper end to form a handle 25, and at the lower end is screw threaded into the keeper 22, and is adapted to bear upon the wings 8 in the manner of a set-screw to retain the wings in adjusted position. It is customary for persons skilled in the use of such instruments to employ but one hand in the adjustment of same. It is usual to grasp one leg of the instrument between the ball of the thumb and third finger, and the other leg between the first finger and adjacent side of the second finger.

The construction of the instrument forming the subject matter hereof is such that when grasping the instrument as described, the lock device on the lower end of the member 6 will fall between the thumb and second finger, whereby the lock may be readily and easily operated when the proper adjustment of the legs has been secured, without changing the grasp upon the instrument, or necessitating the use of the other hand. Therefore the instrument is conducive to rapid and accurate work.

The toggle links 13 also serve to maintain the handle 7 at all times substantially perpendicular to the plane of rotation. In order to facilitate the manufacture, and compensate for inaccuracy in construction, the opening in the member 6 through which the pivot pin 5 extends may be made oblong as at 26 in Fig. 4, and the handle 7 may be formed independent of the member 6 and attached thereto as indicated in said Fig. t.

The lower extremity of the leg 1 is formed tubular as at 27, Figs. 1 and 6. The center point 28 is formed with a tenon or stud 29 adapted to project within thetubular portion of the leg 1, in which it is revolubly adjustable. The fit of the tenon 29 and leg is sufliciently close that the center point will be frictionally held in any point of revoluble adjustment. The lower extremity of the center point 28 is bent out of alinement with the tenon 29, as is obvious upon comparison with the dotted center line in Fig. 1. Thus the bearing point will be rendered slightly eccentric with the leg 1, and by rotating the center point 28 a further adjustment of the operating points ma y be had independent of the pivotal connection of the respective legs.

In Fig. 6 is shown a modification of the connection between the center point and the leg, in which the point is formed wit-h a sleeve or ferrule 30 into which the tubular portion 27 of the leg 1 projects. The operation is similar to that before described.

The leg 2 carries the reversible pencil holder 31. The holder 31 is a channel-like member, the sides of which extend throughout somewhat more than a half circle. One end of the holder 31 is inclined or beveled as at 32, the extreme point being upset or welded into a solid mass as at 33, forming a point, thus enabling the instrument to be employed as a divider. The pencil 34 is inserted in the opposite end of the holder 31, and is secured in position by a set screw 35. The screw 35 extends through a boss or stud 36 projecting from the holder 31, which boss is also screw threaded on its exterior for the reception of a clamp nut 37.

To secure the holder 31 in place it is slipped into the channel of the leg 2 with either the pencil upward as in Fig. 1, or the divider point upward as in Fig. 5, and the stud or boss 36 projecting through a slot or recess 38 formed in the lower end of the leg 2, as indicated in Fig. 3. The clamp nut 37 is adjusted to impinge the lower portion of the leg 2 adjacent to the slot 38 between the nut 37 and the holder 31 as shown in Fig. 2.

In Fig. 5 is shown a modified means of engaging the center point 28 and the holder 31 with the respective legs, comprising a split collar 39 on each of the legs, and an T adjusting screw 40 by which said collar may be tightened upon the parts.

From the above description it will be apparent that there is thus produced an instrument of the type described, possessing the particular points of advantage before enumerated as desirable, but which obviously is susceptible of modification in its form, proportion, detail construction, and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

Having thus described my invention I claim;

1. In an instrument as described, two pivotally connected legs, overlapping wings carried by said legs, said wings projecting inward from the respective legs, below the pivotal connection of said legs, means for clamping the overlapping wings together to lock said legs in predetermined angular relation, substantially as specified.

2. In an instrument as described, the combination with two pivotally connected legs, of overlapping wings carried by the respective legs, a member supported on the pivotal connection of said legs and projecting intermediate said legs, said intermediate projecting member having a recess therein through which said overlapping wings project, locking means carried by said intermediate member and adapted to engage said wings, substantially as specified.

3. In an instrument as described, the combination with two pivotally connected legs, of overlapping wings carried by said legs, a member supported intermediate said legs, locking means for said wings carried by said intermediate member, and means including toggle links supported on the respective legs for automatically maintaining said intermediate member in constant relation with said legs, substantially as specified.

4. In an instrument as described, the combination with two pivotally connected legs, of overlapping wings carried by said legs, locking mechanism, including a revolubly adjustable member, adapted to secure said wings against relative movement, said locking mechanism being located intermediate the respective legs, anc said revoluble member being rotatable in a plane perpendicular to the common plane of said legs, substantially as specified.

5. In an instrument as described, the combination of two pivotally connected legs, a pendent member intermediate said legs and supported on the pivotal connection thereof, a slide adapted to reciprocate on said pendent member, links connecting said slide with the respective legs, overlapping wings carried by the respective legs, lock mechanism carried by said pendent member and adapted to engage said overlapping wings, substantially as specified.

6. In an instrument as described, two pivotally connected legs, a member intermediate said legs having a recess therein, wings carried on the respective legs and adapted to project through the recess in said intermediate member, and an adjustable clamping member cooperating with said interme iate member to lock said wings against movement, substantially as speclfied.

7. In an instrument as described, two legs formed from sheet metal and substantially U shaped in cross section, ears formed on the upper ends of said legs, the ears of one leg overlapping those of the other, a pivotal pin through said cars, a pendent member supported on said pin intermediate the respective ears, said pendent member extending above the pin and forming a handle for the instrument, lock means carried by said pendent member, wings carried by said legs and engaged by said lock means, and means to automatically maintain the pendent member in position to bisect the angle formed by the legs, substantially as specified.

8. In an instrument as described, the combination with two pivotall connected legs, of a reversible pencil holc er formed from sheet metal in the form of an open side tube, one end of which is inclined, upset and welded to form a reinforced divider point, means for retaining a pencil in the opposite end of said reversible holder, and means for removably securing said holder to one of said legs with either end uppermost, substantially as specified.

9. In an instrument as described, the combination with two pivotally connected legs, of a pencil holder having on the end opposite of the pencil point a sharpened point to serve as a divider point, a hollow stud on said member, screw threaded on both the exterior and interior thereof, a set screw within said stud and engaging said pencil, a nut on said stud adapted to engage the holder with one of said legs, substantially as specified.

10. In an instrument as described, a pair of pivotally connected legs, one of which has a notch in the extremity thereof, a reversible pencil holder, a hollow stud )rojeeting therefrom, a set screw extendin through said stud and engaging said pencil a jam nut on said stud, said stud being adapted to extend within the notch in said leg, the portion of the leg adjacent to the notch being gripped between said nut and pencil holder, substantially as specified.

In testimony whereof, I have hereunto set my hand this 14th day of March A. D. 1908.

CHARLES SUMNER EVANS. lVitnesses:

V. A. TROXELL, F. L. WALKER. 

